Apple's 6QQ said why it can't be added from the album when it is added. It used to be possible, but it has been impossible recently; Seek an answer

It should be that icloud cloud synchronization is set in the mobile phone. Without WiFi, the picture can't be seen.

Change the settings of the mobile phone. If the icloud cloud is not synchronized, you won't automatically upload the photos in the album, so the photos in the mobile phone album don't need to be downloaded and watched, but can be added after publishing.